Depends on your definition of goth, if you mean real goth and not this modernday newmetal bollocks or this strange obbsseive labeling of blackmetal etc as goth then Audiogalaxy can get you:
Bauhaus
The Cure
Sisters Of Mercy
Red Lorry Yellow Lorry
Siouxsie And The Banshees

All Classics

If you want newer goth stuff then try MP3.com or Audiogalaxy or similar again for:

The Dream Disciples
Temple Of Rain
The Razor Skyline
Heaven Falls Hard

Alternatively there is the more dancy EBM and Industrial stuff

I quite like:
Illumina
Haujob
NiN (ofcourse
Wumpscut
Leather Strip